In a continuing effort to improve the quality of shipping fruits, we, the inventors, typically hybridize a large number of peach, nectarine, plum, apricot, and cherry seedlings each year. We also grow a lesser number of open pollinated seeds of each of these fruits. The present invention relates to a new and distinct variety of plum tree, which has been denominated varietally as ‘Plumsweet XXI’.
During a typical blooming season we isolate as seed parents both individual and groups of different plum and interspecific trees by covering them with screen houses. A hive of bees is placed inside each such house, and bouquets to provide pollen from different plum, apricot, and interspecific hybrid trees are placed in buckets near the trees approximately every two days for the duration of the bloom. During 2010 one such house containing ‘Plumred X’ interspecific tree (U.S. Plant Pat. No. 19,591) was crossed by us in this manner. To pollinate this interspecific tree, we selected bouquets from several sources of plum trees without keeping specific written details. Upon reaching maturity the fruit from this interspecific tree was harvested, and the seeds were removed, cracked, stratified and germinated as a group with the label “H8”. They were grown as seedlings on their own root in our greenhouse and upon reaching dormancy transplanted to a cultivated area of our experimental orchard located near Le Grand, Calif. in Merced County (San Joaquin Valley). During the summer of 2014 the claimed variety was selected by us as a single plant from the group of seedlings described above. Subsequent to origination of the present variety of plum tree, we asexually reproduced it by budding and grafting in the experimental orchard described above, and such reproduction of plant and fruit characteristics were true to the original tree in all respects. The reproduction of the variety included the use of ‘Nemaguard’ (unpatented) rootstock upon which the present variety was compatible and true to type.
The present variety is similar to its seed parent, ‘Plumred X’ interspecific tree (U.S. Plant Pat. No. 19,591), by being self-unfruitful and by producing fruit that is clingstone in type, red in flesh color, mostly dark red in skin color, firm, juicy, and very sweet, but is distinguished therefrom by having a smaller size tree, by blooming in the late instead of mid season, and by producing fruit that is smaller in size, that is ovate instead of globose in shape, and that matures about thirty days later.
The present variety is most similar to ‘Blackred XXI’ plum tree (U.S. Plant Pat. No. 28,441) by being self-unfruitful, by blooming in the late season, and by producing fruit that is clingstone in type, medium in size, firm, juicy, and very sweet, but is distinguished therefrom by having a smaller size tree and by producing fruit that is darker red in flesh color, that is mostly dark red instead of black in skin color, that is ovate instead of oblate in shape, and that matures about thirty days later.